Docomo, au, or Softbank?

Recently in the cell phone companies, there are several new services appearing. For example, au has "Customer Satisfaction" service and Softbank has "Yoso-gai (unexpected)" service. I watched a news that now Docomo is being a top by far, and au as a second, then Vodafone. The news took a questionnaire to cell phone user and asked which cell phone company they would like to change since MNP service has started. The answer was au by far. I have an image that Docomo is popular and au is very cheap. Vodafone... LOVE Service?? I think Softbank is also going to be popular near future. Which company do you think will be the top in near future?